Although a wide range of materials can be printed by inkjet printing, in practical applications the number of passes may be prohibitively high or the liquid applied may accumulate excessively. If a silver trace is applied, for example, by inkjet printing on paper, subsequent printing over that trace may find the next ink absorbed under the silver. Accordingly, printing a layer over the silver is not achieved by simply applying the subsequent printing.
An important implementation for such a second layer is to print a dielectric layer over a conductive layer of conductor, such as silver. A second conductive trace could be applied to that dielectric layer so as to form a capacitor. More generally, such laminations of conductors and insulators or dielectrics are used to address wiring requirements where signals cross.
Such applications are discussed in a prior art publication titled “Multilayer Inkjet Printing of Biopolymers, OLED's and Other Devices,” authored by Paul Calvert, Glasson Jabber and Yuka Yoshioka, Department of Materials Science and Engineering and Optical Sciences Center, University of Arizona. It discusses applying a dielelectric layer by inkjet prints of epoxy polymerized after prints with amine. However, it does not address the foregoing practical problems of excessive printing passes, excessive liquid accumulation, and migration of the printing off the lower layer.